Yarn take up device for use with belt supported yarns



y 1, 1957 E. HUSUNG ETAL. 2,792,931

YARN TAKE UP DEVICE FOR USE WITH BELT SUPPORTED YARNS Filed Feb. 15, 1956 I $88? v 4 INVENTORIS firmsl'flusmy w Franz lmlzeu United States Patent C YARN TAKE UP DEVICE FOR USE WITH BELT SUPPORTED YARNS Ernest Husung and Franz Lintzen, Grebben, Germany, assignors to American Enka Corporation, Enka, N. C., a corporation of Delaware This invention relates to yarn take up equipment and more particularly to apparatus for taking up a yarn being delivered to a take up point on a belt.

Sometimes in the manufacture of synthetic threads or yarns, such as rayon, it is desirable to lay up courses of yarns either parallel to or zig zag across the run of a supporting belt. Chemical or drying treatments can be readily effected while the yarn is so supported and the yarn can shrink completely without tension. In such cases, in order that the belt surface may be used economically, it is best to lay up the yarn in a zig zag course transversely of the run of the belt. While this type of yarn distribution is desirable from an economy point of view, the collection of the yarns from the belt after the treatment is over presents very considerable difficulties.

It will be appreciated that if a take up device is located at a fixed station along the run of a belt, it will take up yarn at that point only when yarn is being delivered exactly at the rate at which the take up carries it away. Small or large shrinkage effects will cause migration of the point at which the yarn leaves the belt in relation to the fixed take up point. Since this effect tends to be cumulative a serious problem exists in taking the yarn off the belt.

It has been proposed to control migration of the take up point by measuring increments of departure from the selected point with photo cells and impressing the signal upon either the belt or the take up. While this arrangement is theoretically satisfactory, the necessary circuits are complex in design and therefore somewhat expensive to install and maintain. Another proposal is to place a pressure roller on the belt on the take up point in order to provide a fixed take up station. The winding from the pressure roller is effected by a tension control or slipping bobbin. This method is satisfactory when the thread is deposited reotilinearly in relatively small loops in the direction of movement of the belt but when the surface of the belt is fully employed by laying up the threads in zig zag formation the impulses due to tension become untenable owing to the very irregular delivery of the thread supply by the pressure roller.

It is an object of the present invention to overcome the foregoing limitation and to provide for the take up of thread or yarn from the belt under circumstances where the take up point is automatically maintained in a fixed position.

It is proposed, according to the principles of the present invention, to provide a thread guide at the take up point which is extremely sensitive to variation in tension and to control the take up rate as a function of the sensitive movements of the guide.

Gther objects and advantages of this invention will be apparent upon consideration of the following detailed description of a preferred embodimentthereof in conjunction With the annexed drawings wherein:

Figure l is a view in side elevation of a belt having a take up arrangement constructed in accordance with the principles of the present invention,

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Figure 2 is a view at right angles to the view of Figure 1, and

Figure 3 is a plan view of the apparatus of Figures 1 and 2 taken from the plane of the line 3-3.

Referring now in greater detail to the drawings, the reference numeral 10 designates the upper run of a belt onto the surface of which rayon yarn has been laid up in a zig zag path as may be best seen in Figure 3. The treatment to which the yarn may be subjected forms no part of the present invention and in the depicted operation it is assumed that the yarn has been laid up, treated as desired and is ready for collection in package form. lt will be understood that the zig zag nature of the yarn pattern on the belt is controlled by the relative speed of the belt and the traverse which lays the yarn up there- At the point of withdrawal, the yarn is led through a pivoted thread guide 12, a pair of frusto conical rollers 13 and 14 to a package take up device 15 which is rotated in any conventional manner by means not shown and which will include the normal accessoriesof a winding machine, such as a traverse mechanism and pattern control equipment, not shown.

it will be noted that the rollers 13 and 14 abut at a common line of tangency and that the yarn passes between them at the line of this abutment since the rollers 13 and 14 are frusto conical. It is apparent that the surface speed of rollers 13 and 14, assuming a fixed R. P. M., is a function of the diameter at the point where the speed measurement is made. Hence the speed at which yarn is drawn oft depends upon where it is gripped. Toward the base end of rollers 13 and 14 the diameter is large and the surface speed is high for any given R. P. M. Similarly, toward the apex end, the diameter is small and the peripheral speed is low in relation to the R. P. M.

This invention takes advantage of a take up device of the type of rollers 13 and 14 by using the pivoted thread guide 12 which is delicately balanced at 16 for pivotal swinging movement so that it may adjust the position of the yarn in relation to the periphery of the take up rollers 13 and 14 in dependence upon the tension of the yarn running to the take up. If the tension in the yarn is high, there will be a tendency for the bottom of the guide 12 to migrate to the right or counter-clockwise as viewed in Figure 1. This tendency will cause the yarn to be drawn at the ends of rollers 13 and 14 where the peripheral speed is low. This will tend to compensate for the tension which will tend to restore the thread guide to the vertical position which, in turn, will tend to restore the thread guide to the middle of the line of tangency between the take up rollers 13 and 14. On the other hand, if the yarn on the belt tends to lead the take up, the tension being very low, there is a tendency then to rotate the thread guide 12 clockwise about the pivot at 16, thereby to cause the yarn to be propelled by the surfaces of the rollers 13 and 14 which have large diameters and hence high peripheral speed. This again results in automatic adjustment of the thread guide to the vertical position.

The thread guide 12 is a structure that looks very much like a triangular ladder. It has a loop 17 at its base defined by the smooth wire of which it is made. This loop 17 is about as wide as the thread pattern on the belt and it allows the thread or yarn to enter the thread guide easily from any position across the width of the belt. Above the oval guide 17, adjacent to the belt, there are a series of transverse bars 18. These are, in fact, snubbers and the yarn is led zig zag over one, under the next, and so on to the top thread guide 119 at the apex of the triangular frame 12. This arrangement can best be understood by reference to Figure 1. The thread or yarn "guide 1 24s suspended in-such a way that the lower sectionpthatis the lever arm below the pivot at 16 is about four times as long as the length of the lever arm thereabove. To improve the sensitivity of the guide it may be made of very light material such as polished aluminum.

In order to insure slip free operation of the fnusto conical rollers 13 and 14 it has been found desirable to surface one of them with soft rubber while the other is surfaced in polished steel or hard rubber.

What is claimed is: V

1. A thread guiding assembly comprising a belt for supporting a length of yarn thereon in a zig zag course across its width, take up means presenting a yarn take up surface of varying peripheral speed along its length, a triangular thread guide for guiding the yarn from the belt to said take up means, said thread guide having a yarn receiving loop at'its base commensurate with the width of the yarn course on the belt and having an eye at its apex, and means mounting said thread guide for pivotal movement-in response to tension variations in said yarn to select the compensating position along the length of said take up means.

2. A thread guiding assembly comprising a belt for supporting a length of yarn thereon in a zig zag course across its width, a pair of frusto conical draw oil rollers mounted above the belt in mutual peripheral contact to take up yarn therebetween, a generally fiat triangular thread guide having an oval yarn receiving loop at its base and an eye at its apex, said oval being commensurate with the width of the yarn courses on the belt and means freely pivoting said guide on an axis transverse of the 4 "run at "said belt and nearerthe apex than the base and of said guide. v

3. A thread guiding assembly comprising a belt for supporting a length of yarn thereon in a zig zag course across its width, 21 pair of frusto conical draw off rollers mounted above the belt in mutual peripheral contact to take up yarn therebetween, a generally fiat triangular thread guide defined of light metal wire and having an oval yarn receiving loop at its base end, an eye at its apex connected to the loop by sideframes and rung like bars extending between said side frames in parallelism to said base end guide and means freely pivoting said guide on an axis transverse to the run of said belt, parallel to said rungs and nearer the apex than the base of said guide. p

4. A thread guiding assembly comprising a belt for supporting a length of yarn thereon in a zig zag course across its width, a pair of frusto conical draw oif rollers mounted above the belt in mutual peripheral contact to take up yarn therebetween, a generally flat triangular thread guide defined of light rnetal wire and having 'an oval yarn receiving loop at its base end, an eye at its apex connected to the loop by side frames and rung like bars extending between said side frames in parallelism to said base end guide and means freely pivoting said guide on an axis transverse to the run of said belt, parallel to said rungs and so located that the distance from the pivot to the contact line of the rollers is about A the length of the guide below the pivotv References-Cited in the file of this patent UNITED STATES PATENTS 2,333,278 True'sdail NOV. 2, 1943 

